Safety fuse-switch.



C. L. MATTHEWS & W.A. HEINRICH.

SAFETY FUSE SWITCH.

' APPLICATION FILED APR. 13. 1912.

1 ,288,951.- r Patented Dec.24, 1918. i

2 SHEETSSHEET 1. 1

WIVZAT/O/L flaw/kiwi C/m/de L. Waffems UNITED STATES PATENT OFFICE.

CLAUDE L. MATTHEWS AND WALTER A. HEINRICH, OF ST. LOUIS, MISSOURI, ASSIGN- ORS TO W. N. MATTHEWS AND BROTHER, INCL, OF ST. LOUIS, MISSOURI, A CORPO- RATION OF NEW MEXICO.

SAFETY FUSE-SWITCH.

To all whom it may concern:

Be it known that we, CLAUDE L. MAT- THEWS and WALTER A. HEINRICH, citizens of the United States, residing at the city of St. Louis, State of Missouri, have invented a certain new and useful Improvement in Safety F use-Switches, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification.

This invention relates broadly to electrical distribution apparatus and specifically to certain improvements in fuse switches It is designed particularly as an improvement on the form of fuse switch disclosed in United States Letters Patent No. 986,03 t issued March 7, 1911, to Sylvester B. Way and John L. Fay.

The invention has as its principal object the provision of a fuse switch arrangement which will contribute materially to the safety of such devices particularly in the manipulation thereof in the replacement of a blown fuse.

The invention also contemplates the provision of an arrangement whereby the fuse box or casing in which the fuse switch is housed, is protected from injury consequent uponthe blowing of a fuse.

Other and further ob'ects will be obvious or pointed out hereina ter, reference being had to the accompanying drawings, in which Figure l is a perspective view of the base member showing the line terminal contacts;

Fig. 2 is a perspective of the fuse-carrying switch member;

Fig. 3 is a longitudinal vertical section through the housing;

Fig. 4 is a detail illustrating the upper fuse contact terminal in vertical section;

Fig. 5 is a detail illustrating the lower fuse contact terminal in elevation;

Fig. 6 is a longitudinal vertical section through an improved form of housing;

Fig. 7 is a detail illustrating the spring detent for holding the door in open position;

Specification of Letters Patent.

Patented Dec. 24, 1918.

Application filed April 13, 1917. Serial No. 161,721.

Fig. 8 is a detail illustrating the spring detent for holding the door in closed position;

Fig. 9 is a bottom view of the signal device.

Referring to these illustrations by means of the reference numerals applied, let it be understood that the numeral 1 designates a suitable housing or casing in the nature of a box of any suitable material which is properly equlpped to be attached to a pole or other support upon which the device is to be mounted. This box or housing is closed at one side by a suitable door 2'hinged to the casing and operable in the manner hereinafter to be described. Within the housing is mounted an insulating base member 3 of dielectric material suitably secured in place and spaced apart from the wall of the housing upon which it is mounted by insulating spacers 3 Adjacent the lower portion of the base member 3 is mounted a bracket 4 havin a stud or pintle 5 and forming a {)nountmg for the fuse-carrying switch mem- The fuse-carrying switch member, as will be best observed in Figs. 2, 4 and 5, includes a lower contact terminal member 6 of conductive material, as red brass or copper, provided adjacent one extremity with a transverse channel 6* adapted to fit on the pintle 5. The member 6 is further rovided with a longitudinal channel 6 openln at its upper end and at its forward side. nel is mounted the fuse casing 7 of insulating material, the same being in' the form of a tube of the proper size and form to accommodate the desired fuse F.

At the other extremity of the fuse casing there is mounted the upper fuse contact member 9, which is provided with a lon itu dinal channel for the' accommodation 0 the member 7, the two being secured together by binding screw 12. Upon the contact member 9 is also mounted a manipulative member 11 of insulating material, the same having a n this chanserted into the device from the top, the screw 12 being seated in place in the member 9. If the fuse is the proper length, its lower extremity will project from the channelG",

wherefrom it is turned upwardly against the face of the member 6 and secured in place by suitable means 8. This provides a conductive connection between the members 6 and 9 only through the fuse F.

On the insulating base member 3 above the bracket 4: is mounted a line contact terminal 14 of conductive material having the proper resiliency. Connection to a line is made by a suitable lead-in member l6 which passes through a suitable aperture inthe housing. Spaced apart from the member 14 to an extent equal to the interspacing of the members 6 and -9, and similarly secured to the member 3, is the other line terminal contact 13, which is arranged for connection to the line by means of a suitable lead-in member 15.= The bracket 4 and contact terminals 13" and '14 being in alinement, when the fuse-carrying member is disposed in place so as to swing on pintle 5, the memher 6 may be swung into engagement with contact member 1a, and the member 9 into engagement with contact member 18. The

spring tendency.of the members 13 and 1 1 operates to hold the fuse-carrying member in place and to insure a good electrical connection. In this arrangement, connection between the leads 15 and 16 is established through fuse F. In the event the fuse is blown, the repairman, preferably by use of a suitable implement such as a hook, may engage the non-conductive manipulative member 11 and swing the fuse-carrying member on the pivot 5 so as to disengage the members 9 and 6 from the contact terminals 13 and 14. This breaks all electrical connection with the fuse-carrying member and it may be removed from the bracket i in safety, and the blown fuse replaced.

When the fuse-carrying member is replaced on the bracket 1 and in the contacts 13 and 14 after such an operation, it may occur that it is not pressed entirely home to proper position within the contact members 13 and 14, and an imperfect connection may result. To insure the fuse-carrying member always being pressed to proper position, we make the manipulative member 11 of such length that when the fuse-carrying member is in proper position, the manipulative member 11 will make contact with the swinging door of the carrying member is not pressed home, when I a the door is closed the latter will engage the manipulating member-and by the pressure exerted thereonincident to closing the door, will press the fuse-carrying member to proper position.

'In F hinged at'the side, while in the form illustrated'in Fig. 6, the door is hinged at the top so as to swing on a horizontal axis. In the latter form, we propose to make the door of such weight that it will close-itself under the influence of gravity, and we provide a spring detent member 17 adapted to frictionally'engage the door and hold it closed against casual influences such as wind. Also to hold the door in open position while the fuse-carrying member is being removed, we provide the spring detent member 18 pivoted to the bracket 19 on the door and having ig. 3, the ,door,2 is illustrated. as v slot connection with the stud 20. on the wall 1 of the housing. The detent 18 has a,friction portion 18* adapted to coiiperate with the stud 20 under spring pressure so that, when the door is swung to open position, it will be yieldably supported. By virtue. of'this arrangement, the repairman need not touch any part of the housing, as he may engage the member 21 with his hook and throw the door in open position where it will be caught and held by the detent member 18. By exerting light pressure on the door after he has replaced the fuse, itwill be freed from the restraint of the detent member 18 and will swing to closed position by gravity. A further advantage in the employment of the friction detent 17 and the self-closing door,

lies in the fact that it'afi'ords a factor of safety in the event of the blowing of a fuse. Before the gas pressure'within the casing consequent upon the blowing of the fuse could rise to the point where it would burst the casing, it would force the door open, freeing it from the friction detent 17, and thus permit the gases to escape. Thereupon, the door would resume its closed position by gravity.

As a means for providing a visual signal to indicate that afuse has been blown, we employ the arrangement illustrated in Figs. 6 and 9 wherein it will be observed that the bottom 22 of the housing is provided with an aperture below the opening of the channel 6".' As aclosure for this opening, we arrange on the outer side of the bottom, a sheet 24 of mlca or similar fire-resistant materal, which is permanently attached to the bottom .by means of a fastening 25 in which it may ture.

any suitable means such as the staples 26 which straddle corners of the sheet 24, and from which staples the sheet may be withdrawn by suitable pressure. Upon the blowing of a fuse, the jet of gas from the channel 6 will impinge upon the member 24: and force it from the staples 26 to its pendant position, in which position it will attract the attention of the inspector or repairman. In the arrangement illustrated, the resiliency of the sheet 24 holds it in place in the staples 26, and its flexibility permits its being forced from engagement therewith;

It is to be observed from the foregoing description of our improvements, that the device provides in the first place a very simple fuse-carrying member comprising a minimum number. of parts, and one in which the fuse is thoroughly protected from external injury and yet quickly accessible for replacement. The mounting of the fusecarrying member is such as to permit its being entirely removed from electrical connection with the line before it is removed from its mounting, which circumstance increases the marginof safety for the operator. Likewise, the proper replacement of the fuse in association withithe line terminals is insured by the fact that the housing can not be closed while the fuse-carrying member is in improper position; consequently, the provision of a structure whereby the door is self-closing, renders the proper seating of the fuse-carrying member automatic. The factor ofsafety for the device itself is increased by virtue of the nature of the closure which, by virtue of its friction detent latching device, is held closed against ordinary influences, but may be opened by exceptional pressure within the housing to permit the equalization of the pressure without injury to the struc Finally, an improved form of signal device is employed which will indicate on the exterior of the housing to an inspector the condition of the fuse.

The self-closing door structure with its retaining means and the visual signal device are not herein specifically claimed, inasmuch as said structures are fully disclosed and claimed in ourcopending applications.

Having described different embodiments of our invention which have been put in practice and which in our present belief illustrate the best mode of applying the principles thereof, we are at the. same time aware that the invention may be embodied in other forms all of which it is our purpose to include within the comprehension of the following claims:

What. we claim is:

1. In a safety fuse switch device, the combination of line contact members insulated from each other, a fuse carrying member 'to afford access hinged at one end and adapted to be swung into position to make electrical contact with said line contact members, a projecting member onsaid fuse'carrying member, and a housing for inclosing the contact members and fuse carrying member, said housing including a door portion movable to afford access to the fuse carrying member, which door is adapted to engage the projecting member on said fuse carrying member and move the latter into engagement with both contact memberswhen the door is closed.

2. In a safety switch device, the combination of a housing, contact terminals disposed therein, and a switch member pivotally mounted within the housing and positioned so as to be swung into contact with the terminals; a non-conducting member projecting from said switch member, said housing including a door portion movable to the switch member and engage the non-conducting member to force the switch member into electrical cooperation with the contact terminals,

3. In a device of the class described, the combination of door portion,

a housing having a movable contact terminals disposed therein and insulated from the housing and from each other, a fuse-carrying member hinged within said housing and adapted to be swung into position to engage both contact terminals, and a dielectric member forming an operative connection between the fuse-carrying member and'the movable door member whereby the former is moved to operative position by closing movement of the latter.-

4. Inasafety fuse switch device, the combination with a housing having a movable door portion, of line contact members arfrom each hinged at contact members and ranged within said housing and insulated into position to'make electrical contact with both of said members, and a dielectric member carried by the free end of said fuse carrying member and adapted to be engaged by the door of the housing when the same-is closed whereby said fuse carrying member is moved into engagement with both line contact members.

5. In a safety fuse switch device, the combination with a housing having a movable door portion, of line contact members arranged within said housing and insulated from each other, a fuse carrying member hinged at one end adjacent to one of said contact members and adapted to be swung into position to make electrical contact with both of said members, a dielectric member carried by the free end of said fuse carrying member and adapted to be engaged by the door of the housing when the same is closed, whereby said fuse carrying member our signatures, in the presence of two Wii is moved into engagement with both line nesses, this tenth day of April, 1917. contact members, and there being an aper- CLAUDE L. MATTHEWS. ture formed in said dielectric member, WALTER A. HEINRICH. 5 which aperture is adapted to accommodate Witnesses:

a manipulating instrument. JULIUS E. BENDER,

In testimony whereof We hereunto afiix WILTON A. KAMMAN. 

